Flotation process



' April 29 1924. A 1,491,863

T. A. JNNEY FLOTATION PROCESS Filed oct. 21. 1920 INI/EN TOR.l

Patented Apr. 29, 1924..

SATS THOMAS A. JNNEY,

or GARFIELD, UTAH.

FLOTATION' PROCESS.

Application le October 21, `1920. Serial No. 418,486.

To all whom z't may concem:

Be it known that I, THOMAS A. JANNEY, a citizen of the United States, residing at Garfield, in the county of Salt Lake and State of Utah, have invented cert-ain new and useful` Improvements in 'Flotation Processes, of which the following is a specification.

This application is a continuation in part of mv prior application Serial No. 262,812, filed November 16, 1918.

This invention relates to improvements in the concentration of mineral-bearing ores by the fiotation process and to improvements in oils for use in said process, which is now 'usually performed by subjecting the Wet ore pulp to sub-aeration or to agitation in contact with air after adding to the pulp a Small quantity of oil or other suitable frothing agent, sometimes with the further addition of sulphuric acid or other acid, whereb a mineral-bearing froth is' formed whichy may be oated off Vor otherwise separated from the mixture.

My invention is based on the discovery that if coal tar or Wood oils are used in the flotation process better metallurgical results will be obtained if such oils are reconstructed with sodium sulphide (Na2S) or other suitable reagents, whereby the oils are rendered more easily emulsifiable. I have found that the action of the oil as a metalliferous selective agent is further improved by reconstructing it with sulphur, as hereinafter described. The invention is particularly a plicable to wood oils and to oils of cru e coal tar, or a combination of both. For example, the present output of Wood oils and certain oils of crude coal tar, are not easily emulsifiable and fail to give satisfactory results in the flotation process. It has been found that these oils may be reconstructed with certain reagents as hereinafter described, whereby they are put in such a state that they are very easily emulsified and give results which are far superior tothe results obtained with oil not so treated.,

In carrying out the process, I refer to use the apparatus illustrated in t e drawings, although it will be understood that various other forms of apparatus may be used in carryingV out the process of reconstructing the oil. This apparatus comprises a tank 10 mounted above a furnace 11 having a fire box 12 and a grate 13. The oil to be treated is placed in this tank through an oil'charging valve 14, and the tank is provided with another inlet opening 111a through which sodium sulphidei or other 'reconstructing reagent is introduced into the tank. A plurality of condensing pipes 15 are connected to the upper part of the tank 10 and are inclined upwardl and rearwardly therefrom as illustrated, eing surrounded through a part of their len th by the water-jacket tubes 16 through w ich a circulation of cold water is maintained in order to effect the. condensation of the contents of the tubes 15. The Water is introduced to the water-jacket through the supply pipe 17 and causes the oil in the condensing pipes to condense and fiow 'back into the tank 10 for further treatment. A safety valve 18 set preferably for five pounds pressure is connected to the upper part of the tank. In the refiux still or condenser, certain parts of the lcontents of the tank which will vaporize at the temperature towhich itis sub]ected, are alternately vaporized and condensed until a thorough unlon of the oil and the sodium sulphide or other reagent is effected.

In reconstructing the oil by means of the process herein described, from one to four per cent by Weight of sodium sulphide ,(Na2S) relative to the Weight of the oil is introduced into' the tank with the oil. A fire is -maintained in the furnace beneath the tank in order to heat the mixture therein t., a sufficient' temperature to cause the agent and the oil to unite; that part of the oil which vaporizes rises in the tubes 15, is condensed therein, .and then returns to the tank. This boiling of the mixture of oil and sodium sulphide is preferably carried on at a temperature of from 275"v F. to 300 F.,

and is continued for a period. of about one hour and a half or until the contentsl of theytank are homogeneous and uniform in character. The reconstructed oil so formed may then be drawn off through the pipe 20 to a suitable storage tank or reservoir.

I have found, however, that .the quality of the oil used in the flotation process may be further improved by boilin the same in the presence of sulphur, and i? it is desired to give the oil this further treatment, the oil after treatment with sodium sulphide is retained in the tank and preferably allowed to cool, after which live per cent by weight of sulphur relative to the weight of the con- Bti tents of the tank is introduced into the tank, preferably in the form of flowers of sulphur. The mixture in the tank is then boiled again at a temperature of from 275 F. to 300 F. for a period of three or four hours. The resulting product is then drawn off and stored for use in the flotation process. rlhe temperature and duration of each treatment may vary somewhat depending on the oil being treated and upon the reagent used.

lt is found that the reconstructed oil formed by this double treatment gives very good results when used in the flotation process. For example, l have found that in treating copper ore by the flotation process with an untreated coal tar oil, the resulting tailing contained .480% of copper, whereas, in another test operation on the same ore under the said conditions with the same oil after it had been reconstructedlwith sodium sulphide and sulphur, the resulting tailing contained only .155% of copper, showing that the oil after being treated with sodium sulphide and sulphur is far superior as a metalliferous selective agent to the oil which has not been so treated.'

It will be understood that the oil ma be used after treatment with sodium sulp ide alone, but, in general, it has been found that the results are further improved b further treatment of the oil with lowers o sulphur. While the operations of treating the oil with sodium sulphide and iiowers of sulphur may preferably be carried on successively, it 1s found that equally satisfactory results for flotation purposes may be obtained by treating the oil with these two compounds or reagents simultaneously. ln addition to sodium sulphide, it is possible to use sulphides of potassium, calcium, phides of the alkali metals and earths. sulphide or after treatment with both sodium sulphide and sulphur, as herein described,

the alkaline is ready for use in concentrating ore by the dotation process which may be carried out, for example, -by mixing the finely crushed ore with water to form a freel flowing pulp, adding a small quantity of t e reconstructed oil, and in some cases a small quantity of sulphuric acid H2S04, agitating the mix ture of oil and ulp in contact with air to form a froth and then se arating the froth, as will be apparent to t ose skilled in the art. By treating the oil with sodium sullphide it is made alkaline and more easily exnuilsiiied, whereby the invention is of par and various other sul.

rlhe oil after treatment with sodium igiene ticular advantage as a treatment forcoal tar oils and other oils which ive an acid reaction before being subjected to my improved process. The results obtained 1n the dotation process are particularly improved when -an alkaline coal tar oil is used.

Although l have described a particular method of carrying out my improved procoperation.

- 2. The process of concentrating ores by otation, which comprises adding to a wet ore pulp a quantity of an acid coal tar oil which has been boiled with sodium sulphide to form a union therewith, and then subject-y ing the mixture to a flotation operation.

3. The process of concentrating ores, which comprises adding to the wet ore pulp a coal tar oil frothing agent having normally an acid reaction which has been rendered alkaline 'by distillation in the presence of an alkaline sulphide, and subjecting the resulting mixture to agitation and aeration to forma mineral bearing froth.

. Il. The process of concentrating ores by flotation, which comprises agitating and aerating the ore pulp with a quantity of coal taroil which has been rendered alkaline by boiling in the presence of sodium sulphide.

5.".l`he process of concentrating ores by flotation, which comprises agitating and i aerating the ore pulp with a quantity of coal tar oil which has been heated in the presence of sodium sulphide and'sulph r.

6. The process of concentrating ores by flotation, which comprises agitating and aerating the ore ulp with a frothing agent comprising a coa `tar oil which has first been heated in the presence of sodium sulphide, and then heated in the presenc of sulphur.

7. The process of concentr ting ores by dotation, which comprises the operations of subjecting to a froth forming operation a wet i lll@ lil@

in the presence of sodium sulphide, then has been treated with ap alkaline sulphide allowing the resulting product to cool, and and sulphur to form a union thereof, and finally distillingY the product again inthe then subjecting the mixture to a froth forml0 .presence of sulphur. in operation.

5 9. The process of concentrating ores by n testimony whereof, I have subscribed flotation, which comprises adding to a wet my name.

ore pulp a quantity of coal tar oil which THOMAS A. JANNEY 

